V2X operation method based on TTI bundling in wireless communication system, and terminal using method

ABSTRACT

The present disclosure provides a method by which a terminal for supporting bundling of a plurality of transmission time intervals (TTIs) performs a vehicle-to-everything (V2X) operation in a wireless communication system, wherein the V2X operation is performed on a specific resource on the basis of multiplexing when sensing is performed in a sensing section and the result thereof shows no available resources.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the National Stage filing under 35 U.S.C. 371 ofInternational Application No. PCT/KR2019/008845, filed on Jul. 17, 2019which claims the benefit of Korean Application No. 10-2018-0084656,filed on Jul. 20, 2018, the contents of which are all herebyincorporated by reference herein in their entirety.

BACKGROUND OF THE DISCLOSURE Field of the Disclosure

The present disclosure relates to wireless communication and, moreparticularly, to a V2X operation method based on transmission timerinterval (TTI) bundling in a wireless communication system and aterminal (or user equipment (UE)) using the method.

Related Art

Recently, in 3GPP standardization organization, it has been considered anetwork slicing technique for implementing a plurality of logicalnetworks on a single physical network in the NR system, which is 5Gwireless communication system. To this end, the logical networks needsto be capable of supporting services having various requirements (e.g.,enhanced Mobile Broadband (eMBB), massive Machine Type Communication(mMTC), Ultra Reliable Low Latency Communication (URLLC), etc.). Inaddition, in the physical layer system of the NR system, it has beenconsidered a technique for supporting an orthogonal frequency divisionmultiplexing (OFDM) scheme in which a variable numerology is applicableaccording to the various services. In other words, in the NR (New RAT)system, an OFDM scheme (or a multiple access scheme) in whichindependent numerologies are applied in each time and frequency resourceregion may be supported.

Meanwhile, as a method for increasing reliability of a messagetransmitted by a terminal, a method of bundling and transmitting aplurality of TTIs by accumulating energy in a time axis may beconsidered. Here, in the case of performing TTI bundling, more resourcesare occupied than in the case of not performing TTI bundling, and thus,it is necessary to consider a method for a V2X terminal (or basestation) to use resources more efficiently.

Therefore, the present disclosure provides a method of performing a V2Xoperation by a terminal based on multiplexing and a device using thesame.

SUMMARY OF THE DISCLOSURE

The present disclosure provides a V2X operation method based ontransmission timer interval (TTI) bundling in a wireless communicationsystem and a terminal using the method.

In an aspect, a method for performing a vehicle-to-everything (V2X) by auser equipment (UE) that supports bundling of a plurality oftransmission time intervals (TTIs) in a wireless communication system isprovided. The method may comprise sensing in a sensing period andperforming the V2X operation on a specific resource based onmultiplexing if there is no available resource as a result of thesensing.

The UE may determine that there is no available resource as the resultof the sensing if there is no resource that another UE does not use inthe sensing period.

The UE may determine that there is no available resource as the resultof the sensing if there is a resource that another UE does not use inthe sensing period and a channel busy ratio (CBR) of the resourceexceeds a specific threshold value.

The UE may reserve the specific resource based on a reference signalreceived power (RSRP) of a resource that another UE uses.

The UE may reserve the specific resource in unit of a plurality ofbundled TTIs.

The UE may perform the V2X operation on the specific resource based oncode division multiplexing (CDM).

The UE may transmit a scheduling assignment (SA) including code-relatedinformation.

The UE may transmit the SA at every data transmission time.

The UE may perform the V2X operation on the specific resource based onmultiplexing in a spatial domain.

The UE may transmit an SA including port-related information.

In another aspect, a user equipment (UE) supporting bundling of aplurality of transmission timer intervals (TTIs) is provided. The UE maycomprise a transceiver configured to transmit and receive a wirelesssignal and a processor operatively coupled with the transceiver, whereinthe processor is configured to sense in a sensing period, and to performa V2X operation on a specific resource based on multiplexing if there isno available resource as a result of the sensing.

In other aspects, a method for transmitting information related to avehicle-to-everything (V2X) operation by a base station that supportsbundling of a plurality of transmission time intervals (TTIs) in awireless communication system is provided. The method may comprisetransmitting the information related to the V2X operation to a userequipment (UE), wherein the information related to the V2X operation isinformation related to performing the V2X operation by the UE on aspecific resource based on multiplexing.

According to the present disclosure, reliability of a messagetransmitted by a terminal is increased by providing TTI bundling. Inaddition, in the present disclosure, since multiplexing is used when aV2X operation is performed by applying TTI bundling, a small amount ofresources may be occupied even though TTI bundling is performed. Thus, aV2X terminal may use resources more efficiently.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a wireless communication system.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane.

FIG. 3 is a diagram showing a wireless protocol architecture for acontrol plane.

FIG. 4 shows an example of a downlink/uplink (DL/UL) slot structure in awireless communication system.

FIG. 5 illustrates a downlink (DL) subframe structure used in the 3GPPLTE/LTE(-A) system.

FIG. 6 illustrates a structure of an uplink subframe used in the 3GPPLTE/LTE(-A) system.

FIG. 7 illustrates a system structure of a new generation radio accessnetwork (NG-RAN) to which NR is applied.

FIG. 8 illustrates functional partitioning between NG-RAN and 5GC.

FIG. 9 illustrates a system architecture to which a D2D operation isapplied.

FIG. 10 illustrates an example of a resource unit on time and frequencyresource.

FIG. 11 schematically illustrates an example of a frame structure in theNR system.

FIG. 12 schematically illustrates another example of a frame structurein the NR system.

FIG. 13 schematically shows the types of V2X services and requirementsfor them.

FIG. 14 schematically illustrates an example of TTI bundling.

FIG. 15 is a flowchart of a method of performing a V2X operation basedon multiplexing according to an embodiment of the present disclosure.

FIG. 16 schematically shows an example of a method of multiplexing in aCDM method between terminals in case of TTI bundling.

FIG. 17 is a flowchart of a method of performing a V2X operation basedon multiplexing from a terminal perspective according to an embodimentof the present disclosure.

FIG. 18 is an example of a block diagram of a device for performing aV2X operation based on multiplexing from a terminal perspectiveaccording to an embodiment of the present disclosure.

FIG. 19 is a flowchart of a method for transmitting information relatedto a V2X operation from a base station perspective according to anembodiment of the present disclosure.

FIG. 20 is a block diagram of a device for transmitting informationrelated to a V2X operation from a base station perspective according toan embodiment of the present disclosure.

FIG. 21 illustrates a communication system 1 applied to the presentdisclosure.

FIG. 22 illustrates a wireless device applicable to the presentdisclosure.

FIG. 23 illustrates a signal processing circuit for a transmissionsignal.

FIG. 24 shows another example of a wireless device applied to thepresent disclosure.

FIG. 25 illustrates a portable device applied to the present disclosure.

FIG. 26 illustrates a vehicle or an autonomous vehicle to which thepresent disclosure is applied.

FIG. 27 illustrates a vehicle applied to the present disclosure.

FIG. 28 illustrates an XR device applied to the present disclosure.

FIG. 29 illustrates a robot applied to the present disclosure.

FIG. 30 illustrates an AI device applied to the present disclosure.

DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, terms or abbreviations that are not separately defined maybe defined in 3GPP TS 36 series or TS 38 series.

FIG. 1 illustrates a wireless communication system. The wirelesscommunication system may also be referred to as an evolved-UMTSterrestrial radio access network (E-UTRAN), or long term evolution(LTE)/LTE-A system.

The E-UTRAN includes at least one base station (BS) 20 which provides acontrol plane and a user plane to a user equipment (UE) 10. The UE 10may be fixed or mobile, and may be referred to as another terminology,such as a mobile station (MS), a user terminal (UT), a subscriberstation (SS), a mobile terminal (MT), a wireless device, etc. The BS 20is generally a fixed station that communicates with the UE 10 and may bereferred to as another terminology, such as an evolved node-B (eNB), abase transceiver system (BTS), an access point, etc.

The BSs 20 are interconnected by means of an X2 interface. The BSs 20are also connected by means of an S1 interface to an evolved packet core(EPC) 30, more specifically, to a mobility management entity (MME)through S1-MME and to a serving gateway (S-GW) through S1-U.

The EPC 30 includes an MME, an S-GW, and a packet data network-gateway(P-GW). The MME has access information of the UE or capabilityinformation of the UE, and such information is generally used formobility management of the UE. The S-GW is a gateway having an E-UTRANas an end point. The P-GW is a gateway having a PDN as an end point.

Layers of a radio interface protocol between the UE and the network canbe classified into a first layer (L1), a second layer (L2), and a thirdlayer (L3) based on the lower three layers of the open systeminterconnection (OSI) model that is well-known in the communicationsystem. Among them, a physical (PHY) layer belonging to the first layerprovides an information transfer service by using a physical channel,and a radio resource control (RRC) layer belonging to the third layerserves to control a radio resource between the UE and the network. Forthis, the RRC layer exchanges an RRC message between the UE and the BS.

FIG. 2 is a diagram showing a wireless protocol architecture for a userplane. FIG. 3 is a diagram showing a wireless protocol architecture fora control plane. The user plane is a protocol stack for user datatransmission. The control plane is a protocol stack for control signaltransmission.

Referring to FIGS. 2 and 3 , a PHY layer provides an upper layer with aninformation transfer service through a physical channel. The PHY layeris connected to a medium access control (MAC) layer which is an upperlayer of the PHY layer through a transport channel. Data is transferredbetween the MAC layer and the PHY layer through the transport channel.The transport channel is classified according to how and with whatcharacteristics data is transferred through a radio interface.

Data is moved between different PHY layers, that is, the PHY layers of atransmitter and a receiver, through a physical channel. The physicalchannel may be modulated according to an Orthogonal Frequency DivisionMultiplexing (OFDM) scheme, and use the time and frequency as radioresources.

The functions of the MAC layer include mapping between a logical channeland a transport channel and multiplexing and demultiplexing to atransport block that is provided through a physical channel on thetransport channel of a MAC Service Data Unit (SDU) that belongs to alogical channel. The MAC layer provides service to a Radio Link Control(RLC) layer through the logical channel.

The functions of the RLC layer include the concatenation, segmentation,and reassembly of an RLC SDU. In order to guarantee various types ofQuality of Service (QoS) required by a Radio Bearer (RB), the RLC layerprovides three types of operation mode: Transparent Mode (TM),Unacknowledged Mode (UM), and Acknowledged Mode (AM). AM RLC provideserror correction through an Automatic Repeat Request (ARQ).

The RRC layer is defined only on the control plane. The RRC layer isrelated to the configuration, reconfiguration, and release of radiobearers, and is responsible for control of logical channels, transportchannels, and PHY channels. An RB means a logical route that is providedby the first layer (PHY layer) and the second layers (MAC layer, the RLClayer, and the PDCP layer) in order to transfer data between UE and anetwork.

The function of a Packet Data Convergence Protocol (PDCP) layer on theuser plane includes the transfer of user data and header compression andciphering. The function of the PDCP layer on the user plane furtherincludes the transfer and encryption/integrity protection of controlplane data.

What an RB is configured means a procedure of defining thecharacteristics of a wireless protocol layer and channels in order toprovide specific service and configuring each detailed parameter andoperating method. An RB can be divided into two types of a Signaling RB(SRB) and a Data RB (DRB). The SRB is used as a passage through which anRRC message is transmitted on the control plane, and the DRB is used asa passage through which user data is transmitted on the user plane.

If RRC connection is established between the RRC layer of UE and the RRClayer of an E-UTRAN, the UE is in the RRC connected state. If not, theUE is in the RRC idle state.

A downlink transport channel through which data is transmitted from anetwork to UE includes a broadcast channel (BCH) through which systeminformation is transmitted and a downlink shared channel (SCH) throughwhich user traffic or control messages are transmitted. Traffic or acontrol message for downlink multicast or broadcast service may betransmitted through the downlink SCH, or may be transmitted through anadditional downlink multicast channel (MCH). Meanwhile, an uplinktransport channel through which data is transmitted from UE to a networkincludes a random access channel (RACH) through which an initial controlmessage is transmitted and an uplink shared channel (SCH) through whichuser traffic or control messages are transmitted.

Logical channels that are placed over the transport channel and that aremapped to the transport channel include a broadcast control channel(BCCH), a paging control channel (PCCH), a common control channel(CCCH), a multicast control channel (MCCH), and a multicast trafficchannel (MTCH).

The physical channel includes several OFDM symbols in the time domainand several subcarriers in the frequency domain. One subframe includes aplurality of OFDM symbols in the time domain. An RB is a resourcesallocation unit, and includes a plurality of OFDM symbols and aplurality of subcarriers. Furthermore, each subframe may use specificsubcarriers of specific OFDM symbols (e.g., the first OFDM symbol) ofthe corresponding subframe for a physical downlink control channel(PDCCH), that is, an L1/L2 control channel. A Transmission Time Interval(TTI) is a unit time for subframe transmission.

FIG. 4 shows an example of a downlink/uplink (DL/UL) slot structure in awireless communication system. In particular, FIG. 4 shows a structureof a resource grid of a 3GPP LTE (-A) system. There is one resource gridper antenna port.

A slot includes a plurality of orthogonal frequency divisionmultiplexing (OFDM) symbols in a time domain and includes a plurality ofresource blocks (RBs) in a frequency domain. The OFDM symbol also refersto one symbol interval. Referring to FIG. 4 , a signal transmitted ineach slot may be represented by a resource grid including N^(DL/DL)_(RB)*N^(RB) _(sc) subcarriers and N^(DL/UL) _(symb) OFDM symbols. Here,N^(DL) _(RB) denotes the number of resource blocks (RBs) in a downlinkslot, and N^(UL) an denotes the number of RBs in a UL slot. N^(DL) _(RB)and N^(UL) _(RB) depend on a DL transmission bandwidth and a ULtransmission bandwidth, respectively. N^(DL) _(symb) denotes the numberof OFDM symbols in the downlink slot, and N^(UL) Symb denotes the numberof OFDM symbols in the UL slot. N^(RB) _(sc) denotes the number ofsubcarriers constituting one RB.

An OFDM symbol may be called an SC-FDM (Single Carrier FrequencyDivision Multiplexing) symbol according to a multiple access scheme. Thenumber of OFDM symbols included in a slot may depend on a channelbandwidth and the length of a cyclic prefix (CP). For example, a slotincludes 7 OFDM symbols in the case of normal CP and 6 OFDM symbols inthe case of extended CP. While FIG. 4 illustrates a subframe in which aslot includes 7 OFDM symbols for convenience, embodiments of the presentdisclosure may be equally applied to subframes having different numbersof OFDM symbols. Referring to FIG. 4 , each OFDM symbol includesN^(DL/UL) _(RB)*N^(RB) _(sc) subcarriers in the frequency domain.Subcarrier types may be classified into a data subcarrier for datatransmission, a reference signal subcarrier for reference signaltransmission, and null subcarriers for a guard band and a direct current(DC) component. The null subcarrier for a DC component is a subcarrierremaining unused and is mapped to a carrier frequency (f₀) during OFDMsignal generation or frequency up-conversion. The carrier frequency isalso called a center frequency.

One RB is defined by N^(DL/UL) _(symb) (e.g., 7) consecutive OFDMsymbols in the time domain and N^(RB) _(sc) (e.g. 12) consecutivesubcarriers in the frequency domain. For reference, a resource composedof an OFDM symbol and a subcarrier is called a resource element (RE) ora tone. Accordingly, an RB is composed of N^(DL/DL) _(symb)*N^(RB)_(sc). Each RE in the resource grid may be uniquely defined by an indexpair (k, l) in a slot. Here, k is an index in the range of 0 toN^(DL/UL) _(RB)*N^(RB) _(sc)−1 in the frequency domain and 1 is an indexin the range of 0 to N^(DL/UL) _(symb)−1.

Two RBs that occupy N^(RB) _(sc) consecutive subcarriers in a subframeand respectively disposed in two slots of the subframe are called aphysical resource block (PRB) pair. Two RBs constituting a PRB pair havethe same PRB number (or PRB index). A virtual resource block (VRB) is alogical resource allocation unit for resource allocation. The VRB hasthe same size as that of the PRB. The VRB may be divided into alocalized VRB and a distributed VRB depending on a mapping scheme of VRBinto PRB. The localized VRBs are mapped into the PRBs, whereby VRBnumber (VRB index) corresponds to PRB number. That is, N^(DL)_(PRB)=N^(DL) _(RB) is obtained. Numbers are given to the localized VRBsfrom 0 to N^(DL) _(VRB)-1, and N^(DL) _(VRB)=N^(DL) _(RB) is obtained.Accordingly, according to the localized mapping scheme, the VRBs havingthe same VRB number are mapped into the PRBs having the same PRB numberat the first slot and the second slot. On the other hand, thedistributed VRBs are mapped into the PRBs through interleaving.Accordingly, the VRBs having the same VRB number may be mapped into thePRBs having different PRB numbers at the first slot and the second slot.Two PRBs, which are respectively located at two slots of the subframeand have the same VRB number, will be referred to as an VRB pair.

FIG. 5 illustrates a downlink (DL) subframe structure used in the 3GPPLTE/LTE(-A) system.

A DL subframe is divided into a control region and a data region in atime domain. Referring to FIG. 3 , a maximum of 3 (or 4) OFDM symbolslocated in a front part of a first slot of a subframe correspond to thecontrol region. Hereinafter, a resource region for PDCCH transmission ina DL subframe is referred to as a PDCCH region. OFDM symbols other thanthe OFDM symbol(s) used in the control region correspond to the dataregion to which a physical downlink shared channel (PDSCH) is allocated.Hereinafter, a resource region available for PDSCH transmission in theDL subframe is referred to as a PDSCH region. Examples of a DL controlchannel used in 3GPP LTE include a physical control format indicatorchannel (PCFICH), a physical downlink control channel (PDCCH), aphysical hybrid ARQ indicator channel (PHICH), etc. The PCFICH istransmitted in the first OFDM symbol of a subframe and carriesinformation about the number of OFDM symbols available for transmissionof a control channel within a subframe. The PHICH carries a HARQACK/NACK as a response to UL transmission.

Control information transmitted via a PDCCH is referred to as downlinkcontrol information (DCI). The DCI includes resource allocationinformation for a UE or a UE group and other control information. Forexample, the DCI includes transmission format and resource allocationinformation of a DL shared channel (DL-SCH), transmission format andresource allocation information of a UL shared channel (UL-SCH), paginginformation on a paging channel (PCH), system information on a DL-SCH,resource allocation information of a higher-layer control message suchas a random access response transmitted on a PDSCH, a transmission (Tx)power control command set for individual UEs in a UE group, a Tx powercontrol command, activation indication information of voice over IP(VoIP), etc. The size and usage of the DCI carried by one PDCCH may bechanged according to DCI format and the size of the DCI may be changedaccording to a coding rate.

A plurality of PDCCHs may be transmitted in a PDCCH region of a DLsubframe. A UE may monitor a plurality of PDCCHs. A BS decides a DCIformat according to DCI to be transmitted to a UE and attaches a cyclicredundancy check (CRC) to the DCI. The CRC is masked (or scrambled) withan identifier (e.g. a radio network temporary identifier (RNTI))according to an owner or usage of the PDCCH. If the PDCCH is for aspecific UE, a cell-RNTI (C-RNTI) of the UE may be masked to the CRC. Ifthe PDCCH is for a paging message, a paging identifier (e.g. paging-RNTI(P-RNTI)) may be masked to the CRC. If the PDCCH is for systeminformation (more specifically, a system information block (SIB)), asystem information identifier and a system information RNTI (SI-RNTI)may be masked to the CRC. If the PDCCH is for a random access response,a random access-RNTI (RA-RNTI) may be masked to the CRC. CRC masking (orscrambling) includes an XOR operation of a CRC and an RNTI at a bitlevel, for example.

A PDCCH is transmitted on one control channel element (CCE) or anaggregate of a plurality of consecutive CCEs. The CCE is a logicalallocation unit used to provide a coding rate to a PDCCH based on aradio channel state. The CCE corresponds to a plurality of resourceelement groups (REGs). For example, one CCE corresponds to 9 REGs andone REG corresponds to 4 REs. Four QPSK symbols are mapped to each REG.An RE occupied by an RS is not included in an REG. Accordingly, thenumber of REGs within a given OFDM symbol is changed according topresence/absence of an RS. The REG concept is also used for other DLcontrol channels (i.e. a PCFICH and a PHICH). A DCI format and thenumber of DCI bits are determined according to the number of CCEs.

CCEs are numbered and consecutively used. In order to simplify adecoding process, a PDCCH having a format composed of n CCEs may startfrom only a CCE having a number corresponding to a multiple of n. Thenumber of CCEs used to transmit a specific PDCCH, that is, a CCEaggregation level, is determined by a BS according to channel state. Forexample, in case of a PDCCH for a UE having a good DL channel (e.g. a UEadjacent to a BS), one CCE may be sufficient. However, in case of aPDCCH for a UE having a bad channel (e.g. a UE located at a cell edge),8 CCEs may be required to obtain sufficient robustness. FIG. 6illustrates a structure of an uplink subframe used in the 3GPPLTE/LTE(-A) system.

Referring to FIG. 6 , a UL subframe may be divided into a data regionand a control region in the frequency domain. One or several PUCCHs maybe allocated to the control region to deliver UCI. One or several PUSCHsmay be allocated to the data region of the UL subframe to deliver userdata. The control region and the data region in the UL subframe may alsobe referred to as a PUCCH region and a PUSCH region, respectively. Asounding reference signal (SRS) may be allocated to the data region. TheSRS is transmitted on the last OFDM symbol of the UL subframe in thetime domain and is transmitted on a data transmission band, that is, adata region, of the UL subframe in the frequency domain. SRSs of severalUEs, which are transmitted/received on the last OFDM symbol of the samesubframe, can be distinguished according to a frequencylocation/sequence.

If a UE employs an SC-FDMA scheme in UL transmission, in a 3GPP LTErelease-8 or release-9 system, a PUCCH and a PUSCH cannot besimultaneously transmitted on one carrier in order to maintain a singlecarrier property. In a 3GPP LTE release-10 system, support/non-supportof simultaneous transmission of a PUCCH and a PUSCH may be indicated byhigher layers.

In the UL subframe, subcarriers spaced apart from a DC subcarrier areused as the control region. In other words, subcarriers corresponding toboth ends of a UL transmission bandwidth are assigned to UCItransmission. The DC subcarrier is a component remaining unused forsignal transmission and is mapped to the carrier frequency f₀ duringfrequency up-conversion. A PUCCH for a UE is allocated to an RB pairbelonging to resources operating at a carrier frequency and RBsbelonging to the RB pair occupy different subcarriers in two slots.Assignment of the PUCCH in this manner is represented as frequencyhopping of an RB pair allocated to the PUCCH at a slot boundary. Whenfrequency hopping is not applied, the RB pair occupies the samesubcarrier.

Hereinafter, a new radio access technology (new RAT) will be described.The new RAT may be abbreviated as new radio (NR).

As more communication devices demand larger communication capacities,there is a need for improved mobile broadband communication as comparedto the existing radio access technologies (RAT). Massive machine typeCommunications (MTC), which connects multiple devices and objects toprovide various services anytime and anywhere, is also one of the majorissues to consider in next-generation communication. In addition,communication system design considering services/terminals that aresensitive to reliability and latency has been discussed. Theintroduction of next-generation wireless access technologies consideringsuch enhanced mobile broadband communication, massive MTC,ultra-reliable and low latency communication (URLLC), and the like, hasbeen discussed, and the corresponding technology is referred to as newRAT or NR for the convenience sake in the present disclosure.

FIG. 7 illustrates a system structure of a new generation radio accessnetwork (NG-RAN) to which NR is applied.

Referring to FIG. 7 , the NG-RAN may include a gNB and/or an eNBproviding a user plane and a control plane protocol termination to aterminal. FIG. 4 illustrates a case of including only the gNB. The gNBand eNB are connected to each other by an Xn interface. The gNB and eNBare connected to a 5G Core Network (5GC) through an NG interface. Morespecifically, the gNB and eNB are connected to the access and mobilitymanagement function (AMF) through an NG-C interface and connected to auser plane function (UPF) through an NG-U interface.

FIG. 8 illustrates functional partitioning between NG-RAN and 5GC.

Referring to FIG. 8 , the gNB may provide inter-cell radio resourcemanagement (RRM), radio bearer (RB) control, connection mobilitycontrol, radio access control, measurement configuration & provision,dynamic resource allocation, and the like. An AMF may provide functionssuch as NAS security, idle state mobility handling, and the like. A UPFmay provide functions such as mobility anchoring, PDU handling, and thelike. A session management function (SMF) may provide functions such asUE IP address allocation, PDU session control, and the like.

<D2D (Device-to-Device) Operation>

Hereinafter, it is described the components for device-to-devicecommunication (D2D) technique.

FIG. 9 illustrates a system architecture to which a D2D operation isapplied.

In FIG. 9 , a UE means a user UE, but in the case that a networkequipment like an eNB transmits and receives a signal according to acommunication scheme between UEs, the network equipment like an eNB mayalso be regarded as a kind of UE.

Hereinafter, UE1 may be operated to select a resource unit correspondingto a specific resource in a resource pool that means a set of a seriesof resources and transmit a D2D signal by using the correspondingresource unit.

UE2, which is a reception UE for the transmission, may be configuredwith a resource pool in which UE1 may transmit a signal and may detectthe signal of UE1.

Here, the resource pool may be informed by an eNB in the case that UE1is within a connection coverage of the eNB, and may be informed byanother UE or determined as a predetermined resource in the case that UE1 is out of a connection coverage of the eNB.

Generally, a resource pool includes multiple resource units, and each UEmay select one or multiple resource units and use the one or multipleresource units in its own D2D signal transmission.

FIG. 10 illustrates an example of a resource unit on time and frequencyresource.

The example of FIG. 10 corresponds to the case that the entire frequencyresource resources are divided by NF, and the entire time resources aredivided by NT, and accordingly total NF*NT resource units are defined.

In the example of FIG. 10 , the resource pool is repeated in a period ofNT subframe. Distinctively, a single resource unit may be presentrepeatedly as shown in FIG. 10 . Alternatively, in order to obtaindiversity effect in a time or frequency domain, an index of a physicalresource unit which is mapped to a single logical resource unit may bechanged in a predetermined pattern depending on a time.

In such a resource unit architecture, a resource pool may mean a set ofresource units that a UE intended to transmit a D2D signal uses in atransmission.

The resource pool described above may be sub divided into several types.First, the resource pool may be distinguished according to a content ofa D2D signal which is transmitted in each resource pool.

As an example, the contents of the following D2D signal may bedistinguished, and a separate resource pool may be configured for eachof them.

Scheduling Assignment (SA) or D2D (Sidelink) Control Channel:

A signal including information such as a position of resource of a D2Ddata channel transmitted in a subsequent or a same subframe (SF) by eachtransmission UE, MCS (modulation and coding scheme) or MIMO (MultipleInput Multiple Output) transmission scheme required to demodulate otherdata channel, and a timing advance.

This signal may be transmitted with being multiplexed with D2D data onthe same resource unit, and in this case, a SA resource pool may mean apool of resources in which SA and D2D data are multiplexed andtransmitted. This may also be called the other name, D2D (sidelink)control channel.

D2D Data Channel:

A pool of resources that a transmission UE uses for transmitting userdata by using a resource designated by SA.

In the case that it is available to be multiplexed with D2D data andtransmitted on the same resource unit, in the resource pool for D2D datachannel, only the D2D data channel excluding SA information istransmitted.

In other words, the resource element which was used for transmitting theSA information in an individual resource unit in a SA resource pool isstill used for transmitting D2D data in the D2D data channel resourcepool.

Discovery Channel:

A resource pool for a message in which information such as an ID of atransmission UE is transmitted and enables for an adjacent UE todiscover the transmission UE.

Even in the case that a content of D2D signal described above is thesame, depending on a transmission and reception attribute of D2D signal,different resource pool may be used.

As an example, even in the case of the same D2D data channel or adiscovery message, depending on a transmission timing determinationscheme of a D2D signal (e.g., whether it is transmitted on a receptiontiming of synchronization reference signal or transmitted by applying apredetermined timing advance), a resource allocation scheme (e.g.,whether a transport resource of an individual signal is designated by aneNB to an individual transmission UE or an individual transmission UEselects an individual signal transport resource autonomously in a pool),a signal format (e.g., the number of symbols occupied by each D2D signalin a subframe or the number of subframes used for transmitting a singleD2D signal), a signal strength from an eNB or a transmission powerstrength of a D2D UE, it may be further distinguished as differentresource pool.

For the convenience of description, in a D2D communication, a methodthat an eNB directly indicates a transport resource of a D2Dtransmission UE is called Mode 1, and a transport resource region ispreconfigured or a method that an eNB designates a transport resourceregion and a UE directly selects a transport resource is called Mode 2.

For a D2D discovery, a case that an eNB directly indicates a resource iscalled Type 2, and a case that a UE directly selects a transportresource in a preconfigured resource region, or a resource regionindicated by an eNB is called Type 1.

The above mentioned D2D may also be called sidelink, and SA may becalled physical sidelink control channel (PSCCH). A D2D synchronizationsignal may be called sidelink synchronization signal (SSS), and thecontrol channel for transmitting the most basic information before a D2Dcommunication transmitted with the SSS may be called Physical sidelinkbroadcast channel (PSBCH), or in other name, Physical D2Dsynchronization channel (PD2DSCH).

A signal for a specific UE to inform that the UE is present in aneighbor may include an ID of the specific UE, and such a channel may becalled physical sidelink discovery channel (PSDCH).

In Rel. 12 D2D, only a D2D communication UE transmits PSBCH togetherwith SSS, and owing to this, a measurement of SSS is performed by usinga DMRS of PSBCH. An out-coverage UE measures a DMRS of PSBCH andmeasures RSRP of the signal and determines whether the UE itself becomesa synchronization source.

<NR (New RAT)>

As more communication devices require a greater communication capacity,there emerges a need for enhanced mobile broadband communicationcompared to the existing radio access technology (RAT). In addition,massive machine type communications (MTC) providing various servicesanywhere and at any time by connecting multiple devices and things isalso one of important issues to be taken into consideration in thenext-generation communication. Furthermore, the design of acommunication system in which services/UEs sensitive to reliability andlatency are taken into consideration is also discussed.

As described above, the introduction of a next-generation RAT in whichenhanced mobile broadband (eMBB) communication, massive MTC (mMTC) andultra-reliable and low latency communication (URLLC) are taken intoconsideration is now discussed. In the present disclosure, thecorresponding technology is commonly called NR, for convenience sake.

<Frame Structure for NR>

FIG. 11 schematically illustrates an example of a frame structure in theNR system.

Referring to FIG. 11 , the frame structure of NR is characterized in theself-contained structure that includes all of DL control channel, DL orUL data, UL control channel, and the like in a single frame unit.

At this time, in the DL control channel, DL data scheduling information,UL data scheduling information, and the like may be transmitted, and inthe UL control channel, ACK/NACK information for DL data, CSIinformation (modulation and coding scheme information, MIMO transmissionrelated information, etc.), a scheduling request, and the like may betransmitted.

In FIG. 11 , a time gap for DL-to-UL or UL-to-DL switching may bepresent between the control region and the data region.

In addition, one of DL control/DL data/UL data/UL control may not beconfigured in a single frame. Alternatively, an order for each channel(e.g., DL control/DL data/UL control/UL data or UL control/UL data/DLcontrol/DL data, etc.) included in a single frame may be changed.

The frame structure of the NR system described with the example of FIG.8 may be distinguished into 4 types as shown in FIG. 9 , largely.

FIG. 12 schematically illustrates another example of a frame structurein the NR system.

Type A: DL Control+DL Data

That is, according to Type A, a single slot (or frame) includes a DLcontrol region and a DL data region.

Type B: UL Data+UL Control

That is, according to Type B, a single slot (or frame) includes a ULdata region and a UL control region. Here, the UL control may be omittedin dynamic manner.

Type C: DL Control+DL Data+GP (Guard Period)+UL Control

That is, according to Type C, a single slot (or frame) includes a DLcontrol region, a DL data region, a GP (guard period) region and a ULcontrol region.

Type D: DL Control+GP+UL Data+UL Control

That is, according to Type D, a single slot (or frame) includes a DLcontrol region, a GP region, a UL data region and a UL control region.Here, the positions of the UL data and the UL control may be changed, orthe UL control may be omitted in dynamic manner.

<Analog Beamforming>

In a millimeter wave (mmW) system, since a wavelength is short, multipleantenna elements may be installed in the same area. That is, consideringthat the wavelength at 30 GHz band is 1 cm, a total of 100 antennaelements may be installed in a 5 by 5 cm panel at intervals of 0.5lambda (wavelength) in the case of a 2-dimensional array. Therefore, inthe mmW system, it is available to improve the coverage or throughput byincreasing the beamforming (BF) gain using multiple antenna elements.

In this case, in the case that each antenna element may include atransceiver unit (TXRU) to enable adjustment of transmit power andphase, independent beamforming per frequency resource is available.However, installing TXRUs in all of the about 100 antenna elements isless feasible in terms of cost. Therefore, a method of mapping aplurality of antenna elements to one TXRU and adjusting a direction of abeam using an analog phase shifter has been considered. However, theanalog beamforming method is disadvantageous in that frequency selectivebeamforming is impossible because only one beam direction is generatedover the entire band.

As an intermediate form of digital beamforming (BF) and analogbeamforming (BF), hybrid BF with B TXRUs that are fewer than Q antennaelements may be considered. In this case, the number of beam directionsthat can be transmitted at the same time is limited to B or less, whichdepends on the connection scheme of B TXRUs and Q antenna elements.

Hereinafter, the present disclosure will be described.

The aforementioned D2D communication may be extended and applied tosignal transmission/reception between vehicles, and communicationrelated to vehicles is specifically called V2X (vehicle-to-everything)communication. In V2X, the term “X” is pedestrian (communication betweena vehicle and a device carried by an individual), vehicle (communicationbetween vehicles) (V2V), infrastructure/network (communication between avehicle and a roadside unit (RSU)/network (ex) RSU is a transportationinfrastructure entity (ex) an entity transactions or a stationary UE))(V2I/N), etc. A device (related to V2P communication) possessed by apedestrian (or person) is named “P-UE”, and a device (related to V2Xcommunication) installed in a vehicle is named “V-UE”. In the presentdisclosure, the term “ENTITY” may be interpreted as at least one ofP-UE, V-UE, and RSU (/network/infrastructure).

Here, as an example, a V2X communication mode may be divided into (A) amode (MODE #3) in which the base station signals (/controls) V2X messagetransmission (/reception)-related scheduling information (on a V2Xresource pool pre-configured (/pre-signaled)) (representatively) (from(the base station (/network)) in case of following a mode (e.g., LTE(A)operated based on an instruction of the base station (e.g., a UE locatedwithin base station communication coverage (and/or in an RRC_CONNECTEDstate) is a main target) and/or (B) a mode (MODE #4) in which a UE(autonomously) determines (/controls) V2X message transmission(/reception)-related scheduling information (a V2X resource poolpre-configured (/pre-signaled) from a base station (/network)) in casewhere a terminal (or user equipment (UE)) follows a mode (e.g., LTE(A)operated based on sensing or the like with the degree of freedom (e.g.,a UE positioned inside/outside base station communication coverage)(and/or of an RRC_CONNECTED/IDLE state) is a main target).

Here, as an example, in the present disclosure, the wording “sensingoperation” may be interpreted as a PSSCH DM-RS sequence-based PSSCH-RSRPmeasurement operation (scheduled by a decoding-successful PSCCH) and/ora (V2X resource pool-related subchannel-based) S-RSSI measurementoperation.

Meanwhile, a channel busy ratio (CBR) may be defined to support the V2Xoperation. Hereinafter, the CBR will be described in more detail.

A CBR measured in a subframe (or TTI, or slot, or subslot) n may bedefined as follows.

The CBR may refer to a portion of a subchannel in a resource pool inwhich an S-RSSI measured by a UE during a subframe (or TTI, or slot, orsubslot) [n−100, n−1] is detected to exceed a preset threshold withrespect to a PSSCH.

The CBR may refer to a portion of a subchannel in a resource pool inwhich an S-RSSI measured by a UE during a subframe (or TTI, or slot, orsubslot) [n−100, n−1] is detected to exceed a preset threshold withrespect to a PSSCH in a pool in which a physical sidelink controlchannel (PSCCH) is configured to be transmitted in not-neighboringresource blocks along with a PSSCH corresponding to a PSCCH. In thiscase, it may be assumed that the PSCCH pool is configured with resourceshaving the size of two consecutive physical resource block (PRB) pairsin the frequency domain.

The CBR may be applied in an RRC_IDLE intra frequency, RRC_IDLE interfrequency, RRC_CONNECTED intra frequency, and/or RRC_CONNECTED interfrequency.

Here, a subframe (or TTI, or slot, or subslot) index may be based on aphysical subframe (or TTI, or slot, or subslot) index.

Hereinafter, types of V2X services and requirements therefor will bebriefly described with reference to the drawings.

FIG. 13 schematically shows the types of V2X services and requirementsfor them.

According to FIG. 13 , the types of services supported by V2X may beexpressed as a graph in which one axis (i.e., a vertical axis in FIG. 13) represents latency and reliability and the other axis (i.e., ahorizontal axis in FIG. 13 ) represents data rate.

First, as an example of the types of services supported by V2X, theremay be use cases such as latency less than E2E (end-to-end) 100 msec,reliability less than 10¹ error rate and/or basic road safety 1310requiring a data rate less than 100 kbps per vehicle, and/or basicinfotainment 1320.

Here, an example of the basic road safety 1310 may include a forwardcollision warning or the like. An example of the basic infotainment 1320may include traffic flow optimization or the like.

In addition, as another example of the types of services supported byV2X, there may be use cases such as latency less than E2E 10 msec,reliability less than 10⁴ error rate, a data rate less than 1000 Mbpsper vehicle, automated driving 1330 requiring relative position accuracyof 0.1 m between terminals, sensor data dissemination 1340, and/oradvanced infotainment 1350.

Here, examples of the automated driving 1330 may include cooperativecollision avoidance, remote driving, high-density platooning, and thelike. Examples of the sensor data dissemination 1340 may includecollective perception or the like. Examples of the advanced infotainment1350 may include dynamic map update, high-quality multimedia, augmentedreality navigation, and the like.

Meanwhile, in a next-generation communication system, various use casesmay be supported. For example, services for communication such asautonomous vehicles, smart cars, or connected cars may be considered.For these services, each vehicle may exchange information as acommunicatable terminal, select resources for communication with orwithout a help of a BS, and exchange messages between terminals.

In the present disclosure, a new method capable of more efficientlyusing resources, while increasing reliability of a transmission messagewhen resources are allocated in vehicle-to-everything (V2X)communication, is proposed.

In the present disclosure, the inventive matters and/or embodiments maybe regarded as one proposed method, but a combination between eachinventive matter and/or embodiments may also be considered as a newmethod. In addition, the inventive matters are not limited to theembodiments presented in the present disclosure and are not limited to aspecific system.

In the case of all (parameter) and/or (operation) and/or (combinationbetween each parameter and/or operation) and/or (whether thecorresponding parameter and/or operation is applied) and/or (whether acombination of each parameter and/or operations is applied), the BS mayset (in advance) for the terminal through higher layer signaling and/orphysical layer signaling or may be defined in a system in advance.

The TTI of the present disclosure may correspond to a unit of variouslengths such as a sub-slot/slot/subframe or a basic unit which is abasic unit of transmission, and the terminal of the present disclosuremay correspond to various types of devices, such as a vehicle and apedestrian terminal.

As a method for increasing reliability of a message transmitted by theterminal, a method of bundling and transmitting a plurality of TTIs toaccumulate and transmit energy in a time axis may be considered.Hereinafter, the bundling of TTIs will be described with reference tothe drawings.

FIG. 14 schematically illustrates an example of TTI bundling.

According to FIG. 14 , the V2X terminal may bundle a plurality of TTIsand transmit data. Here, bundling a plurality of TTIs to transmit datamay mean that the terminal repeatedly transmits the same data in eachTTI unit within the bundled TTI unit. Here, when the terminal repeatedlytransmits the same data, a redundancy version for each data may bedifferent. This may refer to performing a TTI bundling unit when theterminal reserves transmission resources or the base station allocatestransmission resources of the terminal in V2X communication.

For convenience of understanding, TTI bundling may be described asfollows by applying it to the example of FIG. 14 . For example, whenfour TTIs are bundled, the same data may be repeatedly transmitted foreach of a first TTI, a second TTI, a third TTI, and a fourth TTI amongthe bundled TTIs.

Meanwhile, when TTI bundling is performed, more resources are occupiedthan in a case where TTI bundling is not performed, so it is necessaryto consider a method for the V2X terminal (or base station) to use theresource more efficiently.

Hereinafter, the method for the V2X terminal to use resources moreefficiently will be described in terms of using multiplexing when theterminal performs a V2X operation.

FIG. 15 is a flowchart of a method of performing a V2X operation basedon multiplexing according to an embodiment of the present disclosure.

According to FIG. 15 , a terminal (the first UE in FIG. 15 ) may receiveinformation (e.g., a threshold value for CBR or a threshold value forRSRP, etc.) related to V2X operation from a base station (S1510). Here,the terminal may be a terminal supporting V2X operation. In addition,the terminal may be a terminal that supports bundling for a plurality oftransmission timer intervals (TTIs). In addition, the terminal may be aterminal that operates based on sensing or the like with the degree offreedom. For example, in the example of LTE(-A), the terminal may be aterminal (e.g., mode 4 terminal) that (independently) determines(/controls) scheduling information related to a predetermined(/signaled) V2X message transmission (/reception) (from base station(/network)).

Here, the information related to the V2X operation may be transmittedthrough higher layer signaling (or physical layer signaling) of theterminal, and here, the information related to the V2X operation may bededicated-signaled or broadcast. Here, for example, the higher layersignaling may be application layer signaling, L3 signaling, L2signaling, or the like. For example, physical layer signaling may be L1signaling.

Meanwhile, the information related to the V2X operation may not benecessarily received from the base station. For example, informationrelated to the V2X operation may be preset in the terminal.

A specific example of the information related to the V2X operation willbe described later for convenience of description.

Meanwhile, the terminal may perform sensing in a sensing interval(S1520). Here, the sensing interval may refer to a specific interval inwhich the terminal performs sensing to select and reserve resources forthe V2X operation. The sensing interval here may be expressed as asensing window and the sensing interval may be 1000 ms, for example.

Thereafter, when there is no available resource as a result of thesensing, the terminal may perform the V2X operation on a specificresource based on multiplexing (S1530).

First, as an example in which the UE determines that there is noavailable resource as a result of sensing, the following example mayexist. As an example, if there is no resource not used by anotherterminal in the sensing interval, the terminal may determine that thereis no available resource as a result of the sensing. Or, as an example,if there is a resource not used by another terminal in the sensinginterval but a channel busy ratio (CBR) of the resource exceeds aspecific threshold value, the terminal may determine that there is noavailable resource as a result of the sensing. Hereinafter, a specificexample in which the terminal determines that there is no availableresource as a result of sensing will be described later for convenienceof description.

Meanwhile, the terminal may perform the V2X operation on a specificresource in terms of sensing/selection/reservation as follows. When theterminal performs sensing, the terminal may select a resource in aselection period (or may be expressed as a selection window) as a resultof sensing, reserve resources related to the selected resource(resources having a specific period for the selected resource) for theV2X operation, and perform the V2X operation on the resource(s) (i.e., aspecific resource) reserved for the V2X operation as described above.Here, for example, the selection interval (or selection window) may be100 ms. Applying this to the example of FIG. 15 , when the terminaldetermines that there is no available resource as a result of thesensing, the terminal may reserve a specific resource based onmultiplexing and perform a V2X operation on the reserved specificresource.

Here, for example, the terminal may reserve the specific resource basedon an RSRP of the resource being used by another terminal, and, forexample, the terminal may reserve the specific resource in a unit inwhich the plurality of TTIs are bundled.

Hereinafter, a specific resource and a specific example of reserving (orselecting) a specific resource will be described later for convenienceof description.

Meanwhile, there are largely two methods for the terminal to perform theV2X operation based on multiplexing. One may be code divisionmultiplexing and the other may be multiplexing in the spatial domain.Accordingly, 1. code division multiplexing and 2. multiplexing in thespatial domain will be described hereinafter.

1. Code Division Multiplexing

First, a method of repeatedly transmitting data in each TTI unit withina bundled unit by a terminal and performing code division multiplexing(CDM) between terminals will be described. This may refer to performingin a TTI bundling unit when the terminal reserves transmission resourcesor the base station allocates transmission resources of the terminal inV2X communication. A degradation of capacity resulting from TTI bundlingmay be reduced by increasing resource use efficiency by multiplexing aplurality of terminals in the same resource through code divisionmultiplexing.

A terminal that performs resource reservation to transmit data mayconsider a method of performing multiplexing with a code domain in aresource being used by another terminal when there is no resource notused by the other terminal as a result of the sensing process.

Or, even if there is a resource not used by other terminals, the codedomain multiplexing may be performed in consideration of a congestionsituation when the CBR exceeds a specific threshold, that is, inconsideration of a congestion situation.

Here, the threshold value for the CBR may be defined in advance in thesystem or may be set for the terminal by the base station through higherlayer signaling and/or physical layer signaling (in advance).

Here, which resources being used by other terminals transmission are tobe used by multiplexing with code domain may be an issue.

As one method, a resource with the largest RSRP and a resource with anavailable code may be selected among the resources being used by otherterminals. Here, a near-far problem that may arise in a CDM environmentmay be minimized by selecting the resource with the largest RSRP. Thatis, when transmitting by performing CDM in the same resource, datamultiplexed with different codes are controlled to be received withpower similar to each other in the same resource from the point of viewof the receiving terminal, thereby minimizing the near-far problem.

As another method, when RSRP is measured for a resource being used byanother terminal, it is possible to select an arbitrary resource amongresources exceeding a specific RSRP threshold. This considers the factthat, sensing results may be similar when different terminals thatattempt data transmission exist at similar locations, so if allterminals operate to select a resource with the largest RSRP, differentterminals may simultaneously perform multiplexing using the same code inthe same resource to incase a probability of collision of V2Xcommunication between different terminals. As suggested in the presentdisclosure, when an arbitrary resource is selected among resourcesexceeding a specific RSRP threshold, the probability of occurrence ofthe problem that different terminals use the same code in the sameresource may be lowered.

As described above, the RSRP threshold value here may be defined inadvance in the system or may be set (in advance) for the terminal by thebase station through higher layer signaling and/or physical layersignaling.

For the above operation, the UE may include code-related informationapplied to the corresponding data in the SA transmission correspondingto the data when transmitting the data, for example, in the form of anindex, so that the other terminal may know the information of the codebeing used for data transmission corresponding to decoded schedulingassignment (SA) (through decoding the SA).

That is, the terminal may transmit the SA including code-relatedinformation, and through this, another terminal that has received the SAincluding the code-related information may know the code-relatedinformation being used in transmission of the received data related tothe SA.

In conjunction with the above operation, for example, when the terminalto transmit data does not have resources that other terminals do not usein the sensing process (or when the CBR is defined in the system or incase of exceeding a specific threshold value (previously) set for theterminal by the base station through higher layer signaling and/orphysical layer signaling), the terminal may arbitrarily select aresource defined in the system, a resource exceeding the RSRP thresholdvalue (previously) set for the terminal by the base station throughhigher layer signaling and/or physical layer signaling (or a resourcewith the largest RSRP), and a resource with an available code remainingin the corresponding data transmission interval through SA decoding,among the resources being used by other terminals.

Here, the terminal (which selects a resource and transmits data bymultiplexing it with the code domain) may include code informationapplied to the corresponding data (e.g., the index of the applied code)in the SA corresponding to the data and transmit the same.

Meanwhile, the SA may be transmitted at every data transmission time.Since the terminal to transmit data may fail to decode the SA, a methodfor the case where the terminal fails to decode the SA is required.

As one possible method, when the terminal transmits data by performingTTI bundling, a time point at which the corresponding TTI bundling unitmay be started for each TTI bundling length may be defined in the systemin advance, or the base station may (previously) set the time point forthe terminal through higher layer signaling and/or physical layersignaling.

As another method, a method in which the terminal may includeinformation on the “TTI bundling size” in which data is transmittedand/or the “transmission order of data corresponding to thecorresponding SA” in the SA (e.g., in the form of an index) and transmitthe same and multiplexing is performed by utilizing it may beconsidered.

The terminal receiving the SA may know the interval of the TTI bundlingunit through the TTI bundling size included and transmitted in the SAand the transmission order of data corresponding to the SA and know thecode information applied to the corresponding TTI bundling unit throughthe code index included and transmitted in the SA as in the aboveoperation. The terminal that wants to transmit data (e.g., the terminalthat has received the SA and wants to transmit data) may determine aninterval and code resource to transmit by referring to the information.For convenience of understanding, the method described above may bedescribed with reference to the drawings as follows.

FIG. 16 schematically shows an example of a method of multiplexing in aCDM method between terminals in case of TTI bundling.

For example, as in the example of FIG. 16 , a situation where UE 1repeatedly transmits data over 4 TTIs by applying a specific orthogonalcover code (OCC) (e.g., [1 −1 −1 1] code) may be assumed.

Here, UE 1 may transmit the “TTI bundling size”, the “transmission orderindex of data corresponding to the SA” and the “code index” applied inthe interval derived therethrough through the SA in each TTI, and UE 2that wants to transmit data (the terminal receiving the SA transmittedby UE 1) may know the length of the remaining interval and codeinformation corresponding to the interval if SA decoding succeeds in theremaining TTI even if it does not perform SA decoding in the first TTIor fails to decode.

In this case, if data is repeatedly transmitted over 2 TTIs, UE 2 maytransmit using a specific OCC (e.g., code [1 1]) from the third TTIamong the resources transmitted by UE 1 and provide correspondinginformation (to UE 1 or another terminal) through SA.

In order to distinguish between a terminal that transmits data byapplying TTI bundling and a terminal that does not, the terminal mayalso include “whether TTI bundling is applied to data transmissioncorresponding to the SA” in SA and transmit the same.

Hereinafter, referring back to FIG. 15 , multiplexing in the spatialdomain will be described.

2. Multiplexing in Spatial Domain

The multiplexing operation may be similarly applied to a spatial domainother than a code domain. That is, it may operate like, for example,MU-MIMO.

To this end, port-related information (used for data transmissioncorresponding to the SA) may be included in an index form, for example,and transmitted, through which other terminals may know information on aport currently being used for data transmission corresponding to the SAthrough decoding on the corresponding SA.

This may be applied to the code division multiplexing operationdescribed above, and the code-related information in the above mattersmay be replaced with port-related information and applied in the samemanner.

For example, when the terminal determines to perform transmission bymultiplexing to a spatial domain in which of the resources used byanother terminal, the terminal may select a resource with the largestRSRP and a resource with available port among the resources used by theother terminal.

When the terminal to transmit data does not have resources that otherterminals do not use in the sensing process (or when the CBR is definedin the system or in case of exceeding a specific threshold value(previously) set for the terminal by the base station through higherlayer signaling and/or physical layer signaling), the terminal mayarbitrarily select a resource defined in the system, a resourceexceeding the RSRP threshold value (previously) set for the terminal bythe base station through higher layer signaling and/or physical layersignaling, and a resource with an available port remaining in thecorresponding data transmission interval through SA decoding, among theresources being used by other terminals. Alternatively, the terminal mayselect a resource having the largest RSRP and a resource in which anavailable port remains in the corresponding data transmission periodthrough SA decoding.

Here, even if the available port remains, the terminal may select thecorresponding resource by limiting it to a case where the number ofports sensed through SA decoding is less than a certain number. Thelimitation in number may be defined in the system or may be set (inadvance) for the terminal by the base station through higher layersignaling and/or physical layer signaling.

A terminal that transmits data by multiplexing to the spatial domain mayinclude port information (e.g., an index of an applied port) applied tothe data in an SA corresponding to the data and transmit the same.

Here, for example, the terminal receiving the SA may know the intervalof the TTI bundling unit through the TTI bundling size included andtransmitted in the SA and the transmission order of data correspondingto the SA and know port information applied to the corresponding TTIbundling unit through the port index included and transmitted in the SAas in the above operation.

A terminal that wishes to transmit data (i.e., a terminal that hasreceived an SA) may determine an interval and port resource to transmitdata by referring to the information.

The information transmitted through the SA to perform the multiplexingoperation in the spatial domain is not limited to the port information,and for example, the number of layers may be transmitted. Moregenerally, a terminal that wants to transmit new data (i.e., a terminalthat has received an SA) may derive a sequence or the like of an RS tobe used for data transmission thereof to multiplex to the spatial domainin the resource already reserved and used by another terminal byutilizing the information transmitted in the SA.

In the above description, the “available port” may correspond to an RSsequence resource available to perform spatial multiplexing.

Meanwhile, in an environment in which multiplexing is performed in aspatial domain and transmission is performed, a condition for performingmultiplexing may be additionally considered as follows.

In order to distinguish the RS port in case of MU-MIMO transmission, itmay be limited to a case where a size of a frequency resource allocatedto data being transmitted after a resource is reserved is the same as asize of a frequency resource to be allocated for data to be transmittedby another terminal that wants to newly transmit data.

However, this limitation on the size of the frequency resource may notbe applied if the RS is divided into a time axis OCC rather than aninter-sequence frequency axis CDM. Also, in this case, when data istransmitted, the data is not repeatedly transmitted in the TTI bundlingunit within the TTI bundling unit but may be transmitted over the entireTTI bundling unit at a low code rate.

Meanwhile, the following contents may be additionally applied to theexample of FIG. 15 .

For the aforementioned operation, it may be necessary to consider alinkage between SA transmission and data transmission resources. Inother words, when data is CDM-ed as described above, it is necessary toconsider a method of multiplexing the SA that allocates thecorresponding data as well.

If the SA is also configured by CDM, there is a disadvantage in that aterminal that newly transmits data should perform blind decoding (BD)for each code used for the CDM when decoding the SA. In addition, in thecase of the transmission order of data transmitted in the correspondingTTI in which the SA in the TTI bundling unit is transmitted as describedabove, a different value should be indicated for each TTI, so in thiscase, it is difficult to implement CDM.

Considering that SA requires fewer resources than data, a scheme ofconfiguring with FDM unlike data may be considered in the case of SA.

In this case, it may be configured in the form of an N:1 linkage (N>=1)between the SA and the data transmission resource. In a situation wherethe SA and the data transmission resource are linked in 1:1, in order tooperate in the above manner, an offset value may be included in andtransmitted in the SA, whereby how far in a resource away from theresource linked in 1:1 data is transmitted may be known.

The corresponding offset value may have a negative or positive value,may be transmitted in the form of an index value, may be defined inadvance in the system in the form of a table, or may be set (in advance)for the terminal by the base station through higher layer signalingand/or physical layer signaling.

In the case of transmission using the FDM scheme, port information usedfor SA transmission may be defined in advance in the system or may beset (in advance) for the terminal by the base station through higherlayer signaling and/or physical layer signaling.

The information is not limited to the port information, and informationcapable of deriving RS sequence information to be used to transmit thecorresponding SA or corresponding RS sequence information may be definedor set (in advance).

When data is repeatedly transmitted for each TTI within the TTI bundlingunit and multiplexing between terminals is performed using OCC, aredundancy version (RV) value for the corresponding data may be fixed(e.g., 0), and information on the RV (e.g., whether the RV value isfixed and/or the RV value) may be defined in advance in the system ormay be set (in advance) for the terminal by the base station throughhigher layer signaling and/or physical layer signaling.

Alternatively, whether to fix the RV value and/or the RV value may bedetermined implicitly according to one of the information included andtransmitted in the SA (e.g., whether TTI bundling has been applied todata transmission corresponding to the SA) or a combination thereof.

In addition, the terminal performing TTI bundling may be switching abeam to obtain a diversity effect, and in this case, the CDM may not beapplied. In other words, it may be limited to perform multiplexing withCDM only when the RV value is the same and/or the beams are the samewithin the TTI bundling unit.

The example of FIG. 15 may be described in terms of a terminal (V2Xterminal) as follows.

FIG. 17 is a flowchart of a method of performing a V2X operation basedon multiplexing from a terminal perspective according to an embodimentof the present disclosure.

According to FIG. 17 , the terminal may sense in a sensing interval(S1610). Here, since a specific example of sensing in the sensinginterval by the terminal is the same as described above, a repeateddescription thereof will be omitted for convenience of description.

When there is no available resource as a result of the sensing, theterminal may perform the V2X operation on a specific resource based onmultiplexing (S1620). Here, since a specific example in which theterminal performs the V2X operation on a specific resource based onmultiplexing is the same as described above, repeated descriptionthereof will be omitted for convenience of description.

FIG. 18 is an example of a block diagram of a device for performing aV2X operation based on multiplexing from a terminal perspectiveaccording to an embodiment of the present disclosure.

Referring to FIG. 18 , a processor 1800 may include a sensing unit 1810and a V2X operation performing unit 1820. Here, the processor 1800 mayrefer to a processor of FIGS. 21 to 30 to be described later.

The sensing unit 1810 may be configured to sense in a sensing interval.Here, since a specific example of sensing in the sensing interval by theterminal is the same as described above, a repeated description thereofwill be omitted for convenience of description.

The V2X operation performing unit 1820 may be configured to perform theV2X operation on a specific resource based on multiplexing if there isno available resource as a result of the sensing. Here, since a specificexample in which the terminal performs the V2X operation on a specificresource based on multiplexing is the same as described above, arepeated description thereof will be omitted for convenience ofdescription.

The example of FIG. 15 is as follows below from the viewpoint of a basestation.

FIG. 19 is a flowchart of a method for transmitting information relatedto a V2X operation from a base station perspective according to anembodiment of the present disclosure.

According to FIG. 19 , the base station may transmit information relatedto the V2X operation (S1910). Here, the information related to the V2Xoperation may be information related to performing the V2X operation bythe terminal on a specific resource based on multiplexing. Since aspecific example of information related to the V2X operation transmittedby the base station is the same as described above, a repeateddescription thereof will be omitted for convenience of description.

FIG. 20 is a block diagram of a device for transmitting informationrelated to a V2X operation from a base station perspective according toan embodiment of the present disclosure.

According to FIG. 20 , a processor 2000 may include an informationtransmission unit 2010. Here, the processor 2000 may mean a processor inFIGS. 21 to 30 to be described later.

The information transmission unit 2010 may be configured to transmitinformation related to the V2X operation. Here, the information relatedto the V2X operation may be information related to performing the V2Xoperation by the terminal on a specific resource based on multiplexing.Since a specific example of the information related to the V2X operationtransmitted by the base station is the same as described above, repeateddescription thereof will be omitted for convenience of description.

Although not limited thereto, various suggestions of the presentdisclosure described above may be applied to various fields requiringwireless communication/connection (e.g., 5G) between devices.

Hereinafter, it will be illustrated in more detail with reference to thedrawings. In the following drawings/description, the same referencenumerals may exemplify the same or corresponding hardware block,software block, or functional block, unless otherwise indicated.

FIG. 21 illustrates a communication system 1 applied to the presentdisclosure.

Referring to FIG. 21 , a communication system 1 applied to the presentdisclosure includes a wireless device, a base station, and a network.Here, the wireless device refers to a device that performs communicationusing a wireless access technology (e.g., 5G new RAT (NR) or long termevolution (LTE) and may be referred to as a communication/wireless/5Gdevice. Although not limited thereto, the wireless devices may include arobot 100 a, vehicles 100 b-1 and 100 b-2, an extended reality (XR)device 100 c, a hand-held device 100 d, a home appliance 100 e, anInternet of things (IoT) device 100 f, and an AI device/server 400. Forexample, the vehicle may include a vehicle equipped with a wirelesscommunication function, an autonomous vehicle, a vehicle capable ofperforming inter-vehicle communication, and the like. Here, the vehiclemay include an unmanned aerial vehicle (UAV) (e.g., a drone). The XRdevice may include augmented reality (AR)/virtual reality (VR)/mixedreality (MR) devices and may be implemented in the form of ahead-mounted device (HMD), a head-up display (HUD) TV provided in avehicle, a smartphone, a computer, a wearable device, a home appliance,a digital signage, a vehicle, a robot, and the like. Portable devicesmay include a smartphone, a smart pad, a wearable device (e.g., smartwatch, smart glasses), a computer (e.g., notebook computer), etc. Homeappliances may include a TV, a refrigerator, and a washing machine. IoTdevices may include a sensor, a smart meter, and the like. For example,the base station and the network may be implemented as a wirelessdevice, and a specific wireless device 200 a may operate as a basestation/network node for other wireless devices.

The wireless devices 100 a to 100 f may be connected to a network 300through a base station 200. An artificial intelligence (AR) technologymay be applied to the wireless devices 100 a to 100 f, and the wirelessdevices 100 a to 100 f may be connected to the AI server 400 through thenetwork 300. The network 300 may be configured using a 3G network, a 4G(e.g., LTE) network, or a 5G (e.g., NR) network. The wireless devices100 a to 100 f may communicate with each other through the base station200/network 300 but may communicate directly (e.g. sidelinkcommunication) without passing through the base station/network. Forexample, the vehicles 100 b-1 and 100 b-2 may perform directcommunication (e.g. V2V (vehicle to vehicle)/V2X (vehicle to everything)communication). In addition, an IoT device (e.g., sensor) may directlycommunicate with other IoT devices (e.g., sensors) or other wirelessdevices 100 a to 100 f.

Wireless communication/connections 150 a and 150 b may be establishedbetween the wireless devices 100 a to 100 f/base station 200 and thebase station 200/wireless devices 100 a to 100 f. Here, wirelesscommunication/connection may be performed through various wirelessaccess technologies (e.g., 5G NR) for uplink/downlink communication 150a and sidelink communication 150 b (or D2D communication). Through thewireless communication/connection 150 a and 150 b, the wireless deviceand the base station/wireless device may transmit/receive wirelesssignals to each other. For example, the wirelesscommunication/connections 150 a and 150 b may transmit/receive signalsthrough various physical channels based on the entire/partial process ofFIG. A1 . To this end, based on various suggestions of the presentdisclosure, at least some of various configuration informationconfiguring processes for transmission/reception of wireless signals,various signal processing processes (e.g., channel encoding/decoding,modulation/demodulation, resource mapping/demapping, etc.), and aresource allocation process, etc. may be performed.

FIG. 22 illustrates a wireless device applicable to the presentdisclosure.

Referring to FIG. 22 , a first device 100 and a second device 200 maytransmit and receive wireless signals through various wireless accesstechnologies (e.g., LTE and NR). Here, {the first device 100, the seconddevice 200} may correspond to {wireless device 100 x, base station 200}and/or {wireless device 100 x, wireless device 100 x) of FIG. 21 }.

The first device 100 may include one or more processors 102 and one ormore memories 104 and may further include one or more transceivers 106and/or one or more antennas 108. The processor 102 may be configured tocontrol the memory 104 and/or the transceiver 106 and may be configuredto implement the functions, procedures, and/or methodsdescribed/suggested above. For example, the processor 102 may processinformation in the memory 104 to generate first information/signal andthen transmit a wireless signal including the first information/signalthrough the transceiver 106. In addition, the processor 102 may receivea wireless signal including second information/signal through thetransceiver 106 and then store information obtained from signalprocessing of the second information/signal in the memory 104. Thememory 104 may be connected to the processor 102 and may store variousinformation related to the operation of the processor 102. For example,the memory 104 may store software code including instructions forperforming some or all of the processes controlled by the processor 102or performing the previously described/suggested procedures and/ormethods. Here, the processor 102 and the memory 104 may be part of acommunication modem/circuit/chip designed to implement wirelesscommunication technology (e.g., LTE, NR). The transceiver 106 may beconnected with the processor 102 and may transmit and/or receivewireless signals through one or more antennas 108. The transceiver 106may include a transmitter and/or a receiver. The transceiver 106 may beused with a radio frequency (RF) unit. In the present disclosure, thewireless device may refer to a communication modem/circuit/chip.

The second device 200 may include one or more processors 202 and one ormore memories 204 and may further include one or more transceivers 206and/or one or more antennas 208. The processor 202 may be configured tocontrol the memory 204 and/or the transceiver 206 and may be configuredto implement the functions, procedures, and/or methodsdescribed/suggested above. For example, the processor 202 may processinformation in the memory 204 to generate first information/signal andthen transmit a wireless signal including the first information/signalthrough the transceiver 206. In addition, the processor 202 may receivea wireless signal including second information/signal through thetransceiver 206 and then store information obtained from signalprocessing of the second information/signal in the memory 204. Thememory 204 may be connected to the processor 202 and may store variousinformation related to the operation of the processor 202. For example,the memory 204 may store software code including instructions forperforming some or all of the processes controlled by the processor 202or performing the previously described/suggested procedures and/ormethods. Here, the processor 202 and the memory 204 may be part of acommunication modem/circuit/chip designed to implement wirelesscommunication technology (e.g., LTE, NR). The transceiver 206 may beconnected with the processor 202 and may transmit and/or receivewireless signals through one or more antennas 208. The transceiver 206may include a transmitter and/or a receiver. The transceiver 206 may beused with a radio frequency (RF) unit. In the present disclosure, thewireless device may refer to a communication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 willbe described in more detail. Although not limited thereto, one or moreprotocol layers may be implemented by one or more processors 102, 202.For example, one or more processors 102, 202 may implement one or morelayers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, andSDAP). One or more processors 102 and 202 may generate one or moreprotocol data units (PDUs) and/or one or more service data units (SDUs)according to the functions, procedures, suggestions, and/or methodsdisclosed in this document. One or more processors 102 and 202 maygenerate messages, control information, data, or information accordingto the functions, procedures, suggestions and/or methods disclosedherein. One or more processors 102 and 202 may generate a signal (e.g.,baseband signal) containing a PDU, an SDU, a message, controlinformation, data or information according to the functions, procedures,suggestions and/or methods disclosed herein and provide the same to oneor more transceivers 106 and 206. One or more processors 102 and 202 mayreceive signals (e.g., baseband signals) from one or more transceivers106 and 206 and obtain an PDU, a SDU, a message, control information,data or information according to the functions, procedures, suggestionsand/or methods disclosed herein.

The one or more processors 102 and 202 may be referred to as acontroller, a microcontroller, a microprocessor, or a microcomputer. Oneor more processors 102 and 202 may be implemented by hardware, firmware,software, or a combination thereof. For example, one or more applicationspecific integrated circuits (ASICs), one or more digital signalprocessors (DSPs), one or more digital signal processing devices(DSPDs), one or more programmable logic devices (PLDs), or one or morefield programmable gate arrays (FPGAs) may be included in one or moreprocessors 102 and 202. The functions, procedures, suggestions and/ormethods disclosed in this document may be implemented using firmware orsoftware, and firmware or software may be implemented to includemodules, procedures, functions, and the like. Firmware or softwareconfigured to perform the functions, procedures, suggestions and/ormethods disclosed in this document may be included in one or moreprocessors 102 and 202, may be stored in one or more memories 104 and204, and may be driven by one or more processors 102 and 202. Thefunctions, procedures, suggestions and or methods disclosed in thisdocument may be implemented using firmware or software in the form ofcodes, instructions and/or a set of instructions.

One or more memories 104, 204 may be connected to one or more processors102 and 202 and may store various types of data, signals, messages,information, programs, codes, instructions, and/or commends. One or morememories 104 and 204 may include ROM, RAM, EPROM, flash memory, harddrive, registers, cache memory, computer readable storage medium, and/orcombinations thereof. One or more memories 104 and 204 may be locatedinside and/or outside one or more processors 102 and 202. In addition,one or more memories 104 and 204 may be connected to one or moreprocessors 102, 202 through various technologies such as wired orwireless connection.

The one or more transceivers 106 and 206 may transmit user data, controlinformation, wireless signals/channels, and the like mentioned in themethods and/or operation flowcharts of this document to one or moreother devices. The one or more transceivers 106 and 206 may receive userdata, control information, wireless signals/channels, and the likementioned in the functions, procedures, suggestions, methods and/oroperational flowcharts, etc. disclosed herein from one or more otherdevices. For example, one or more transceivers 106 and 206 may beconnected to one or more processors 102 and 202 and may transmit andreceive wireless signals. For example, one or more processors 102 and202 may control one or more transceivers 106 and 206 to transmit userdata, control information, or wireless signals to one or more otherdevices. In addition, one or more processors 102 and 202 may control oneor more transceivers 106 and 206 to receive user data, controlinformation, or wireless signals from one or more other devices. Inaddition, one or more transceivers 106 and 206 may be connected to oneor more antennas 108 and 208, and one or more transceivers 106 and 206may be configured to transmit and receive user data, controlinformation, wireless signals/channels, etc. mentioned in the functions,procedures, suggestions, methods and/or operational flowcharts disclosedin this document. In this document, one or more antennas may be aplurality of physical antennas or a plurality of logical antennas (e.g.,antenna ports). One or more transceivers 106 and 206 may convertreceived wireless signal/channel from an RF band signal into a basebandsignal in order to process received user data, control information,wireless signals/channels, etc. using one or more processors 102 and202. One or more transceivers 106 and 206 may convert user data, controlinformation, wireless signals/channels, etc. processed using one or moreprocessors 102 and 202 from a baseband signal to an RF band signal. Tothis end, one or more of the transceivers 106 and 206 may include(analog) oscillators and/or filters.

FIG. 23 illustrates a signal processing circuit for a transmissionsignal.

Referring to FIG. 23 , the signal processing circuit 1000 may include ascrambler 1010, a modulator 1020, a layer mapper 1030, a precoder 1040,a resource mapper 1050, and a signal generator 1060. Although notlimited thereto, the operations/functions of FIG. 23 may be performed inthe processors 102 and 202 and/or the transceivers 106 and 206 of FIG.22 . The hardware elements of FIG. 23 may be implemented in theprocessors 102 and 202 and/or the transceivers 106 and 206 of FIG. 22 .For example, blocks 1010 to 1060 may be implemented in the processors102 and 202 of FIG. 22 . Also, blocks 1010 to 1050 may be implemented inthe processors 102 and 202 of FIG. 22 , and block 1060 may beimplemented in the transceivers 106 and 206 of FIG. 22 .

A codeword may be converted into a wireless signal through the signalprocessing circuit 1000 of FIG. 23 . Here, the codeword is an encodedbit sequence of an information block. The information block may includea transport block (e.g., a UL-SCH transport block, a DL-SCH transportblock). The wireless signal may be transmitted through various physicalchannels (e.g., PUSCH and PDSCH) of FIG. A1 .

Specifically, the codeword may be converted into a scrambled bitsequence by the scrambler 1010. The scramble sequence used for scramblemay be generated based on an initialization value, and theinitialization value may include ID information of a wireless device.The scrambled bit sequence may be modulated by the modulator 1020 into amodulation symbol sequence. The modulation scheme may includepi/2-binary phase shift keying (pi/2-BPSK), m-phase shift keying(m-PSK), m-quadrature amplitude modulation (m-QAM), and the like. Thecomplex modulation symbol sequence may be mapped to one or moretransport layers by the layer mapper 1030. Modulation symbols of eachtransport layer may be mapped to corresponding antenna port(s) by theprecoder 1040 (precoding). An output z of the precoder 1040 may beobtained by multiplying an output y of the layer mapper 1030 by an N*Mprecoding matrix W. Here, N is the number of antenna ports, and M is thenumber of transport layers. Here, the precoder 1040 may performprecoding after performing transform precoding (e.g., DFT transform) oncomplex modulation symbols. Also, the precoder 1040 may performprecoding without performing transform precoding.

The resource mapper 1050 may map modulation symbols of each antenna portto a time-frequency resource. The time-frequency resource may include aplurality of symbols (e.g., CP-OFDMA symbols, DFT-s-OFDMA symbols) in atime domain and may include a plurality of subcarriers in a frequencydomain. The signal generator 1060 may generate a wireless signal fromthe mapped modulation symbols, and the generated wireless signal may betransmitted to another device through each antenna. To this end, thesignal generator 1060 may include an Inverse fast Fourier transform(IFFT) module and a cyclic prefix (CP) inserter, a digital-to-analogconverter (DAC), a frequency uplink converter, and the like.

A signal processing process for a received signal in the wireless devicemay be configured as the reverse of the signal processing process 1010to 1060 of FIG. 23 . For example, the wireless device (e.g., 100 or 200in FIG. 22 ) may receive a wireless signal from the outside through anantenna port/transceiver. The received wireless signal may be convertedinto a baseband signal through a signal restorer. To this end, thesignal restorer may include a frequency downlink converter, ananalog-to-digital converter (ADC), a CP canceller, and a fast Fouriertransform (FFT) module. Thereafter, the baseband signal may bereconstructed into a codeword through a resource de-mapper process, apostcoding process, a demodulation process, and a descramble process.The codeword may be restored to an original information block throughdecoding. Accordingly, a signal processing circuit (not shown) for areception signal may include a signal restorer, a resource demapper, apostcoder, a demodulator, a descrambler, and a decoder.

FIG. 24 shows another example of a wireless device applied to thepresent disclosure. The wireless devices may be implemented in variousforms according to use-examples/services (see FIGS. 21 and 25 to 30 ).

Referring to FIG. 24 , the wireless devices 100 and 200 correspond tothe wireless devices 100 and 200 of FIG. 22 and may include variouselements, components, units/units, and/or modules. For example, thewireless devices 100 and 200 may include a communication unit 110, acontrol unit 120, a memory unit 130, and an additional component 140.The communication unit may include a communication circuit 112 and atransceiver(s) 114. For example, communication circuit 112 may includeone or more processors 102 and 202 and/or one or more memories 104 and204 of FIG. 22 . For example, the transceiver(s) 114 may include one ormore transceivers 106 and 206 and/or one or more antennas 108 and 208 ofFIG. 22 . The control unit 120 may be electrically connected to thecommunication unit 110, the memory unit 130, and the additionalcomponent 140 and control general operations of the wireless device. Forexample, the control unit 120 may control the electrical/mechanicaloperation of the wireless device based on theprogram/code/command/information stored in the memory unit 130. Inaddition, the control unit 120 may transmit the information stored inthe memory unit 130 to the outside (e.g., other communication device)via the communication unit 110 through a wireless/wired interface orstore information received from the outside (e.g., other communicationdevice) via the communication unit 110 through a wireless/wiredinterface in the memory unit 130.

The additional component 140 may be variously configured according tothe type of wireless device. For example, the additional component 140may include at least one of a power unit/battery, an I/O unit, a drivingunit, and a computing unit. Although not limited thereto, the wirelessdevice may be implemented in the form of the robot (FIGS. 21, 100 a),the vehicles (FIGS. 21, 100 b-1, 100 b-2), the XR device (FIGS. 21, 100c), the portable device (FIGS. 21, 100 d), the home appliance (100 e ofFIG. 21 ), the IoT device (100 f of FIG. 21 ), a digital broadcastingterminal, a hologram device, a public safety device, an MTC device, amedical device, a fintech device (or financial device), a securitydevice, a climate/environment device, an AI server/device (400 of FIG.21 ), a base station (200 of FIG. 21 ), and a network node. The wirelessdevice may be a mobile device or may be used in a fixed place dependingon the use-example/service.

In FIG. 24 , the various elements, components, units/units, and/ormodules in the wireless devices 100 and 200 may all be interconnectedthrough a wired interface, or at least some of them may be wirelesslyconnected through the communication unit 110. For example, in thewireless devices 100 and 200, the control unit 120 and the communicationunit 110 may be connected by wire, and the control unit 120 and thefirst units (e.g., 130 and 140) may be connected wirelessly through thecommunication unit 110. In addition, each element, component, unit/unit,and/or module in the wireless devices 100 and 200 may further includeone or more elements. For example, the control unit 120 may beconfigured as one or more processor sets. For example, the control unit120 may include a set of a communication control processor, anapplication processor, an electronic control unit (ECU), a graphicprocessing processor, and a memory control processor. As anotherexample, the memory unit 130 may include a random access memory (RAM), adynamic RAM (DRAM), a read only memory (ROM), a flash memory, a volatilememory, and a non-volatile memory, and/or a combination thereof.

Hereinafter, an implementation example of FIG. 24 will be described inmore detail with reference to the drawings.

FIG. 25 illustrates a portable device applied to the present disclosure.The portable device may include smart phones, smart pads, wearabledevices (e.g., smart watches, smart glasses), and portable computers(e.g., notebook computers). The portable device may be referred to as amobile station (MS), a user terminal (UT), a mobile subscriber station(MSS), a subscriber station (SS), an advanced mobile station (AMS), or awireless terminal (WT).

Referring to FIG. 25 , the portable device 100 may include an antennaunit 108, a communication unit 110, a control unit 120, a memory unit130, a power supply unit 140 a, an interface unit 140 b, and an I/O unit140 c. The antenna unit 108 may be configured as a part of thecommunication unit 110. Blocks 110 to 130/140 a to 140 c correspond toblocks 110 to 130/140 of FIG. 24 , respectively.

The communication unit 110 may transmit and receive signals (e.g., data,control signals, etc.) with other wireless devices and base stations.The control unit 120 may perform various operations by controllingcomponents of the portable device 100. The control unit 120 may includean application processor (AP). The memory unit 130 may storedata/parameters/programs/codes/commands required for driving theportable device 100. Also, the memory unit 130 may store input/outputdata/information, and the like. The power supply unit 140 a may supplypower to the portable device 100 and may include a wired/wirelesscharging circuit, a battery, and the like. The interface unit 140 b maysupport connection between the portable device 100 and other externaldevices. The interface unit 140 b may include various ports (e.g., audioinput/output ports, video input/output ports) for connection withexternal devices. The I/O unit 140 c may receive or output imageinformation/signal, audio information/signal, data, and/or informationinput from a user. The I/O unit 140 c may include a camera, amicrophone, a user input unit, a display 140 d, a speaker, and/or ahaptic module.

For example, in the case of data communication, the I/O unit 140 cacquires information/signals (e.g., touch, text, voice, image, video)input from the user, and the acquired information/signal may be storedin the memory unit 130. The communication unit 110 may convert theinformation/signal stored in the memory into a wireless signal andtransmit the converted wireless signal directly to another wirelessdevice or to a base station. In addition, after receiving a wirelesssignal from another wireless device or a base station, the communicationunit 110 may restore the received wireless signal to the originalinformation/signal. After the restored information/signal is stored inthe memory unit 130, the restored information/signal may be output invarious forms (e.g., text, voice, image, video, haptic) through the I/Ounit 140 c.

FIG. 26 illustrates a vehicle or an autonomous vehicle to which thepresent disclosure is applied. The vehicle or autonomous vehicle may beimplemented as a mobile robot, a vehicle, a train, an aerial vehicle(AV), or a ship.

Referring to FIG. 26 , a vehicle or an autonomous vehicle 100 mayinclude an antenna unit 108, a communication unit 110, a control unit120, a driving unit 140 a, a power supply unit 140 b, a sensor unit 140c, and an autonomous driving unit 140 d. The antenna unit 108 may beconfigured as a part of the communication unit 110. Blocks 110/130/140 ato 140 d correspond to blocks 110/130/140 of FIG. 24 , respectively.

The communication unit 110 may transmit and receive signals (e.g., data,control signals, etc.) with external devices such as other vehicles,base stations (e.g. base stations, roadside base stations, etc.), andservers. The control unit 120 may perform various operations bycontrolling elements of the vehicle or the autonomous vehicle 100. Thecontrol unit 120 may include an electronic control unit (ECU). Thedriving unit 140 a may cause the vehicle or the autonomous vehicle 100to travel on the ground. The driving unit 140 a may include an engine, amotor, a power train, a wheel, a brake, a steering device, and the like.The power supply unit 140 b supplies power to the vehicle or theautonomous vehicle 100 and may include a wired/wireless chargingcircuit, a battery, and the like. The sensor unit 140 c may obtain avehicle status, surrounding environment information, user information,and the like. The sensor unit 140 c may include an inertial measurementunit (IMU) sensor, a collision sensor, a wheel sensor, a speed sensor,an inclination sensor, a weight detection sensor, a heading sensor, aposition module, a vehicle advancement/reverse sensor, a battery sensor,a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, ahumidity sensor, an ultrasonic sensor, an illumination sensor, a pedalposition sensor, etc. The autonomous driving unit 140 d may implement atechnology that maintains a driving lane, a technology thatautomatically adjusts a speed such as adaptive cruise control, atechnology that automatically drives along a predetermined route, and atechnology that automatically sets a route and drives along the routewhen a destination is set.

For example, the communication unit 110 may receive map data, trafficinformation data, and the like from an external server. The autonomousdriving unit 140 d may generate an autonomous driving route and adriving plan based on the acquired data. The control unit 120 maycontrol the driving unit 140 a so that the vehicle or the autonomousdriving vehicle 100 moves along the autonomous driving route accordingto the driving plan (e.g., speed/direction adjustment). Duringautonomous driving, the communication unit 110 mayaperiodically/periodically acquire the latest traffic information datafrom the external server and may acquire surrounding traffic informationdata from nearby vehicles. In addition, during autonomous driving, thesensor unit 140 c may acquire a vehicle state and surroundingenvironment information. The autonomous driving unit 140 d may updatethe autonomous driving route and the driving plan based on newlyacquired data/information. The communication unit 110 may transmitinformation on a vehicle location, the autonomous driving route, and thedriving plan to the external server. The external server may predicttraffic information data in advance using an AI technology or the likebased on information collected from the vehicle or autonomous vehicleand may provide the predicted traffic information data to the vehicle orautonomous vehicle.

FIG. 27 illustrates a vehicle applied to the present disclosure. Thevehicle may also be implemented as means of transportation, trains,aircraft, and ships.

Referring to FIG. 27 , the vehicle 100 may include a communication unit110, a control unit 120, a memory unit 130, an I/O unit 140 a, and apositioning unit 140 b. Here, blocks 110 to 130/140 a to 140 bcorrespond to blocks 110 to 130/140 of FIG. 24 , respectively.

The communication unit 110 may transmit and receive signals (e.g., data,control signals, etc.) with other vehicles or external devices such as abase station. The control unit 120 may perform various operations bycontrolling components of the vehicle 100. The memory unit 130 may storedata/parameters/programs/codes/commands supporting various functions ofthe vehicle 100. The I/O unit 140 a may output an AR/VR object based oninformation in the memory unit 130. The I/O unit 140 a may include anHUD. The positioning unit 140 b may acquire location information of thevehicle 100. The location information may include absolute locationinformation of the vehicle 100, location information within a drivingline, acceleration information, location information with nearbyvehicles, and the like. The positioning unit 140 b may include GPS andvarious sensors.

As an example, the communication unit 110 of the vehicle 100 may receivemap information, traffic information, etc. from the external server andstore the same in the memory unit 130. The positioning unit 140 b mayacquire vehicle location information through GPS and various sensors andstore the vehicle location information in the memory unit 130. Thecontrol unit 120 may generate a virtual object based on map information,traffic information, vehicle location information, and the like, and theI/O unit 140 a may display the generated virtual object on a window ofthe vehicle (1410, 1420). In addition, the control unit 120 maydetermine whether the vehicle 100 is operating normally within a drivingline based on the vehicle location information. When the vehicle 100deviates from the driving line abnormally, the control unit 120 maydisplay a warning on a windshield of the vehicle through the I/O unit140 a. In addition, the control unit 120 may broadcast a warning messageregarding a driving abnormality to nearby vehicles through thecommunication unit 110. Depending on the situation, the control unit 120may transmit location information of the vehicle and information ondriving/vehicle abnormalities to a related organization through thecommunication unit 110.

FIG. 28 illustrates an XR device applied to the present disclosure. TheXR device may be implemented as an HMD, a head-up display (HUD) providedin a vehicle, a television, a smartphone, a computer, a wearable device,a home appliance, a digital signage, a vehicle, a robot, and the like.

Referring to FIG. 28 , the XR device 100 a may include a communicationunit 110, a control unit 120, a memory unit 130, an I/O unit 140 a, asensor unit 140 b, and a power supply unit 140 c. Here, blocks 110 to130/140 a to 140 c correspond to blocks 110 to 130/140 of FIG. 24 ,respectively.

The communication unit 110 may transmit and receive signals (e.g., mediadata, control signals, etc.) with other wireless devices, portabledevices, or external devices such as a media server. The media data mayinclude video, images, and sound. The control unit 120 may performvarious operations by controlling components of the XR device 100 a. Forexample, the control unit 120 may be configured to control and/orperform procedures such as video/image acquisition, (video/image)encoding, and metadata generating and processing. The memory unit 130may store data/parameters/programs/codes/commands required for drivingthe XR device 100 a/generating an XR object. The I/O unit 140 a mayacquire control information, data, etc. from the outside and may outputthe generated XR object. The I/O unit 140 a may include a camera, amicrophone, a user input unit, a display unit, a speaker, and/or ahaptic module. The sensor unit 140 b may obtain an XR device status,surrounding environment information, user information, and the like. Thesensor unit 140 b may include a proximity sensor, an illuminance sensor,an acceleration sensor, a magnetic sensor, a gyro sensor, an inertialsensor, an RGB sensor, an IR sensor, a fingerprint recognition sensor,an ultrasonic sensor, an optical sensor, a microphone, and/or a radar.The power supply unit 140 c supplies power to the XR device 100 a andmay include a wired/wireless charging circuit, a battery, and the like.

As an example, the memory unit 130 of the XR device 100 a may includeinformation (e.g., data, etc.) necessary for generating an XR object(e.g., AR/VR/MR object). The I/O unit 140 a may acquire a command tooperate the XR device 100 a from the user, and the control unit 120 maydrive the XR device 100 a according to the user's driving command. Forexample, when the user tries to watch a movie, news, etc. through the XRdevice 100 a, the control unit 120 may transmit content requestinformation to another device (for example, the portable device 100 b)or a media server through the communication unit 130. The communicationunit 130 may download/stream content such as movies and news fromanother device (e.g., the portable device 100 b) or a media server tothe memory unit 130. The control unit 120 may control and/or performprocedures such as video/image acquisition, (video/image) encoding, andmetadata generating/processing for the content and generate/output an XRobject based on information on a surrounding space or a real objectacquired through the I/O unit 140 a/sensor unit 140 b.

In addition, the XR device 100 a may be wirelessly connected to theportable device 100 b through the communication unit 110, and theoperation of the XR device 100 a may be controlled by the portabledevice 100 b. For example, the portable device 100 b may operate as acontroller for the XR device 100 a. To this end, the XR device 100 a mayacquire 3D location information of the portable device 100 b and thengenerate and output an XR object corresponding to the portable device100 b.

FIG. 29 illustrates a robot applied to the present disclosure. Robotsmay be classified into industrial, medical, household, and militaryrobots depending on the purpose or field of use.

Referring to FIG. 29 , the robot 100 may include a communication unit110, a control unit 120, a memory unit 130, an I/O unit 140 a, a sensorunit 140 b, and a driving unit 140 c. Here, blocks 110 to 130/140 a to140 c correspond to blocks 110 to 130/140 of FIG. 24 , respectively.

The communication unit 110 may transmit and receive signals (e.g.,driving information, control signals, etc.) with other wireless devices,other robots, or external devices such as a control server. The controlunit 120 may perform various operations by controlling components of therobot 100. The memory unit 130 may storedata/parameters/programs/codes/commands supporting various functions ofthe robot 100. The I/O unit 140 a may acquire information from theoutside of the robot 100 and may output information to the outside ofthe robot 100. The I/O unit 140 a may include a camera, a microphone, auser input unit, a display unit, a speaker, and/or a haptic module. Thesensor unit 140 b may obtain internal information, surroundingenvironment information, user information, and the like of the robot100. The sensor unit 140 b may include a proximity sensor, anilluminance sensor, an acceleration sensor, a magnetic sensor, a gyrosensor, an inertial sensor, an IR sensor, a fingerprint recognitionsensor, an ultrasonic sensor, an optical sensor, a microphone, a radar,and the like. The driving unit 140 c may perform various physicaloperations such as moving a robot joint. In addition, the driving unit140 c may cause the robot 100 to travel on the ground or fly in the air.The driving unit 140 c may include an actuator, a motor, a wheel, abrake, a propeller, and the like.

FIG. 30 illustrates an AI device applied to the present disclosure. AIdevices may be implemented as fixed devices or mobile devices such asTVs, projectors, smartphones, PCs, notebooks, digital broadcastingterminals, tablet PCs, wearable devices, set-top boxes (STBs), radios,washing machines, refrigerators, digital signage, robots, vehicles, etc.

Referring to FIG. 30 , the AI device 100 includes a communication unit110, a control unit 120, a memory unit 130, input/output units 140 a and140 b, a learning processor unit 140 c, and a sensor unit 140 d. Blocks110 to 130/140 a to 140 d correspond to blocks 110 to 130/140 of FIG. 24, respectively.

The communication unit 110 may transmit or receive wired/wirelesssignals (e.g., sensor information, user inputs, learning models, controlsignals, etc.) with external devices such as other AI devices (e.g.,FIGS. 21, 100 x, 200, 400) or external devices such as the AI server200. To this end, the communication unit 110 may transmit information inthe memory unit 130 to an external device or may transmit a signalreceived from the external device to the memory unit 130.

The control unit 120 may determine at least one executable operation ofthe AI device 100 based on information determined or generated using adata analysis algorithm or a machine learning algorithm. In addition,the control unit 120 may perform a determined operation by controllingthe components of the AI device 100. For example, the control unit 120may request, search, receive, or utilize data of the learning processorunit 140 c or the memory unit 130 and control components of the AIdevice 100 to execute a predicted operation or an operation determinedto be desirable among at least one executable operation. In addition,the control unit 120 may collect history information including theuser's feedback on the operation content or the operation of the AIdevice 100 and stores the collected history information in the memoryunit 130 or the learning processor unit 140 c or transmit the historyinformation to the external device such as the AI server (400 of FIG. 21). The collected history information may be used to update a learningmodel.

The memory unit 130 may store data supporting various functions of theAI device 100. For example, the memory unit 130 may store data obtainedfrom the input unit 140 a, data obtained from the communication unit110, output data from the learning processor unit 140 c, and dataobtained from the sensing unit 140. In addition, the memory unit 130 maystore control information and/or software codes necessary for theoperation/execution of the control unit 120.

The input unit 140 a may acquire various types of data from the outsideof the AI device 100. For example, the input unit 120 may acquirelearning data for model learning and input data to which the learningmodel is to be applied. The input unit 140 a may include a camera, amicrophone, and/or a user input unit. The output unit 140 b may generateoutput related to visual, auditory, or tactile sensation. The outputunit 140 b may include a display unit, a speaker, and/or a hapticmodule. The sensing unit 140 may obtain at least one of internalinformation of the AI device 100, surrounding environment information ofthe AI device 100, and user information using various sensors. Thesensing unit 140 may include a proximity sensor, an illuminance sensor,an acceleration sensor, a magnetic sensor, a gyro sensor, an inertialsensor, an RGB sensor, an IR sensor, a fingerprint recognition sensor,an ultrasonic sensor, an optical sensor, a microphone, and/or a radar.

The learning processor unit 140 c may train a model composed of anartificial neural network using the learning data. The learningprocessor unit 140 c may perform AI processing together with thelearning processor unit of the AI server (400 of FIG. 21 ). The learningprocessor unit 140 c may process information received from an externaldevice through the communication unit 110 and/or information stored inthe memory unit 130. In addition, an output value of the learningprocessor unit 140 c may be transmitted to an external device throughthe communication unit 110 and/or may be stored in the memory unit 130.

What is claimed is:
 1. A method for performing a sidelink operation by auser equipment (UE) in a wireless communication system, the methodcomprising: receiving, from a base station, information for a resourcepool of a sidelink; performing a measurement of a channel busy ratio(CBR) on the resource pool, wherein the CBR is defined as a portion ofsub-channels in the resource pool whose sidelink received signalstrength indicator (SL RSSI) measured by the UE exceed a thresholdsensed over a CBR measurement window, wherein the CBR is applicable forat least one of a radio resource control (RRC) idle intra frequency, aRRC idle inter frequency, a RRC connected intra frequency, or a RRCconnected inter frequency; and performing the sidelink operation on aspecific resource based on multiplexing based on no available resourcebeing present as a result of sensing during a sensing period, whereinthe UE supports bundling of a plurality of transmission time intervals(TTIs).
 2. The method of claim 1, wherein the UE determines that thereis no available resource as the result of the sensing if there is noresource that another UE does not use in the sensing period.
 3. Themethod of claim 1, wherein the UE determines that there is no availableresource as the result of the sensing if there is a resource thatanother UE does not use in the sensing period and a channel busy ratio(CBR) of the resource exceeds a specific threshold value.
 4. The methodof claim 1, wherein the UE reserves the specific resource based on areference signal received power (RSRP) of a resource that another UEuses.
 5. The method of claim 1, wherein the UE reserves the specificresource in unit of a plurality of bundled TTIs.
 6. The method of claim1, wherein the UE performs the sidelink operation on the specificresource based on code division multiplexing (CDM).
 7. The method ofclaim 6, wherein the UE transmits a scheduling assignment (SA) includingcode-related information.
 8. The method of claim 7, wherein the UEtransmits the SA at every data transmission time.
 9. The method of claim1, wherein the UE performs the sidelink operation on the specificresource based on multiplexing in a spatial domain.
 10. The method ofclaim 9, wherein the UE transmits an SA including port-relatedinformation.
 11. A user equipment (UE) comprising: a transceiverconfigured to transmit and receive a wireless signal; and a processoroperatively coupled with the transceiver, wherein the processor isconfigured to: control the transceiver to receive, from a base station,information for a resource pool of a sidelink; perform a measurement ofa channel busy ratio (CBR) on the resource pool, wherein the CBR isdefined as a portion of sub-channels in the resource pool whose sidelinkreceived signal strength indicator (SL RSSI) measured by the UE exceed athreshold sensed over a CBR measurement window, wherein the CBR isapplicable for at least one of a radio resource control (RRC) idle intrafrequency, a RRC idle inter frequency, a RRC connected intra frequency,or a RRC connected inter frequency; and perform a sidelink operation ona specific resource based on multiplexing, based on no availableresource being present as a result of sensing during a sensing period,wherein the UE supports bundling of a plurality of transmission timeintervals (TTIs).